Re: [PATCH] x86/vmware: Map vTPM as private in encrypted VMs

[sashiko-bot@kernel.org]

> From: Alex James <alex.james@broadcom.com>
> 
> Encrypted VMware guests can use a virtual Trusted Platform Module
> (vTPM) implemented by a paravisor, trusted code running alongside Linux
> inside the protected VM. Its register page needs a private mapping so
> accesses reach the paravisor instead of host device emulation.
> 
> The default ioremap() path maps device registers as shared. Without a
> VMware private-MMIO override, this also applies to the vTPM registers,
> preventing the guest from communicating with the paravisor's TPM.
> 
> Install is_private_mmio() for the vTPM's single register page when guest
> memory encryption is active and firmware supplies a TPM event log. This
> lets ioremap() select a private mapping for the device. Hyper-V already
> does the same for its paravisor vTPM in hv_is_private_mmio(), added by
> commit 812b0597fb40 ("x86/hyperv: Change vTOM handling to use standard
> coco mechanisms").
> 
> [ zack: Moved the include and explained the private-mapping requirement ]
> 
> Signed-off-by: Alex James <alex.james@broadcom.com>
> Signed-off-by: Zack Rusin <zack.rusin@broadcom.com>

Sashiko has reviewed this patch and found no issues.

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